1 /* 2 * pc87427.c - hardware monitoring driver for the 3 * National Semiconductor PC87427 Super-I/O chip 4 * Copyright (C) 2006 Jean Delvare <khali@linux-fr.org> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * Supports the following chips: 16 * 17 * Chip #vin #fan #pwm #temp devid 18 * PC87427 - 8 - - 0xF2 19 * 20 * This driver assumes that no more than one chip is present. 21 * Only fan inputs are supported so far, although the chip can do much more. 22 */ 23 24 #include <linux/module.h> 25 #include <linux/init.h> 26 #include <linux/slab.h> 27 #include <linux/jiffies.h> 28 #include <linux/platform_device.h> 29 #include <linux/hwmon.h> 30 #include <linux/hwmon-sysfs.h> 31 #include <linux/err.h> 32 #include <linux/mutex.h> 33 #include <linux/sysfs.h> 34 #include <linux/ioport.h> 35 #include <asm/io.h> 36 37 static unsigned short force_id; 38 module_param(force_id, ushort, 0); 39 MODULE_PARM_DESC(force_id, "Override the detected device ID"); 40 41 static struct platform_device *pdev; 42 43 #define DRVNAME "pc87427" 44 45 /* The lock mutex protects both the I/O accesses (needed because the 46 device is using banked registers) and the register cache (needed to keep 47 the data in the registers and the cache in sync at any time). */ 48 struct pc87427_data { 49 struct device *hwmon_dev; 50 struct mutex lock; 51 int address[2]; 52 const char *name; 53 54 unsigned long last_updated; /* in jiffies */ 55 u8 fan_enabled; /* bit vector */ 56 u16 fan[8]; /* register values */ 57 u16 fan_min[8]; /* register values */ 58 u8 fan_status[8]; /* register values */ 59 }; 60 61 /* 62 * Super-I/O registers and operations 63 */ 64 65 #define SIOREG_LDSEL 0x07 /* Logical device select */ 66 #define SIOREG_DEVID 0x20 /* Device ID */ 67 #define SIOREG_ACT 0x30 /* Device activation */ 68 #define SIOREG_MAP 0x50 /* I/O or memory mapping */ 69 #define SIOREG_IOBASE 0x60 /* I/O base address */ 70 71 static const u8 logdev[2] = { 0x09, 0x14 }; 72 static const char *logdev_str[2] = { DRVNAME " FMC", DRVNAME " HMC" }; 73 #define LD_FAN 0 74 #define LD_IN 1 75 #define LD_TEMP 1 76 77 static inline void superio_outb(int sioaddr, int reg, int val) 78 { 79 outb(reg, sioaddr); 80 outb(val, sioaddr + 1); 81 } 82 83 static inline int superio_inb(int sioaddr, int reg) 84 { 85 outb(reg, sioaddr); 86 return inb(sioaddr + 1); 87 } 88 89 static inline void superio_exit(int sioaddr) 90 { 91 outb(0x02, sioaddr); 92 outb(0x02, sioaddr + 1); 93 } 94 95 /* 96 * Logical devices 97 */ 98 99 #define REGION_LENGTH 32 100 #define PC87427_REG_BANK 0x0f 101 #define BANK_FM(nr) (nr) 102 #define BANK_FT(nr) (0x08 + (nr)) 103 #define BANK_FC(nr) (0x10 + (nr) * 2) 104 105 /* 106 * I/O access functions 107 */ 108 109 /* ldi is the logical device index */ 110 static inline int pc87427_read8(struct pc87427_data *data, u8 ldi, u8 reg) 111 { 112 return inb(data->address[ldi] + reg); 113 } 114 115 /* Must be called with data->lock held, except during init */ 116 static inline int pc87427_read8_bank(struct pc87427_data *data, u8 ldi, 117 u8 bank, u8 reg) 118 { 119 outb(bank, data->address[ldi] + PC87427_REG_BANK); 120 return inb(data->address[ldi] + reg); 121 } 122 123 /* Must be called with data->lock held, except during init */ 124 static inline void pc87427_write8_bank(struct pc87427_data *data, u8 ldi, 125 u8 bank, u8 reg, u8 value) 126 { 127 outb(bank, data->address[ldi] + PC87427_REG_BANK); 128 outb(value, data->address[ldi] + reg); 129 } 130 131 /* 132 * Fan registers and conversions 133 */ 134 135 /* fan data registers are 16-bit wide */ 136 #define PC87427_REG_FAN 0x12 137 #define PC87427_REG_FAN_MIN 0x14 138 #define PC87427_REG_FAN_STATUS 0x10 139 140 #define FAN_STATUS_STALL (1 << 3) 141 #define FAN_STATUS_LOSPD (1 << 1) 142 #define FAN_STATUS_MONEN (1 << 0) 143 144 /* Dedicated function to read all registers related to a given fan input. 145 This saves us quite a few locks and bank selections. 146 Must be called with data->lock held. 147 nr is from 0 to 7 */ 148 static void pc87427_readall_fan(struct pc87427_data *data, u8 nr) 149 { 150 int iobase = data->address[LD_FAN]; 151 152 outb(BANK_FM(nr), iobase + PC87427_REG_BANK); 153 data->fan[nr] = inw(iobase + PC87427_REG_FAN); 154 data->fan_min[nr] = inw(iobase + PC87427_REG_FAN_MIN); 155 data->fan_status[nr] = inb(iobase + PC87427_REG_FAN_STATUS); 156 /* Clear fan alarm bits */ 157 outb(data->fan_status[nr], iobase + PC87427_REG_FAN_STATUS); 158 } 159 160 /* The 2 LSB of fan speed registers are used for something different. 161 The actual 2 LSB of the measurements are not available. */ 162 static inline unsigned long fan_from_reg(u16 reg) 163 { 164 reg &= 0xfffc; 165 if (reg == 0x0000 || reg == 0xfffc) 166 return 0; 167 return 5400000UL / reg; 168 } 169 170 /* The 2 LSB of the fan speed limit registers are not significant. */ 171 static inline u16 fan_to_reg(unsigned long val) 172 { 173 if (val < 83UL) 174 return 0xffff; 175 if (val >= 1350000UL) 176 return 0x0004; 177 return ((1350000UL + val / 2) / val) << 2; 178 } 179 180 /* 181 * Data interface 182 */ 183 184 static struct pc87427_data *pc87427_update_device(struct device *dev) 185 { 186 struct pc87427_data *data = dev_get_drvdata(dev); 187 int i; 188 189 mutex_lock(&data->lock); 190 if (!time_after(jiffies, data->last_updated + HZ) 191 && data->last_updated) 192 goto done; 193 194 /* Fans */ 195 for (i = 0; i < 8; i++) { 196 if (!(data->fan_enabled & (1 << i))) 197 continue; 198 pc87427_readall_fan(data, i); 199 } 200 data->last_updated = jiffies; 201 202 done: 203 mutex_unlock(&data->lock); 204 return data; 205 } 206 207 static ssize_t show_fan_input(struct device *dev, struct device_attribute 208 *devattr, char *buf) 209 { 210 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 211 struct pc87427_data *data = pc87427_update_device(dev); 212 int nr = attr->index; 213 214 return sprintf(buf, "%lu\n", fan_from_reg(data->fan[nr])); 215 } 216 217 static ssize_t show_fan_min(struct device *dev, struct device_attribute 218 *devattr, char *buf) 219 { 220 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 221 struct pc87427_data *data = pc87427_update_device(dev); 222 int nr = attr->index; 223 224 return sprintf(buf, "%lu\n", fan_from_reg(data->fan_min[nr])); 225 } 226 227 static ssize_t show_fan_alarm(struct device *dev, struct device_attribute 228 *devattr, char *buf) 229 { 230 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 231 struct pc87427_data *data = pc87427_update_device(dev); 232 int nr = attr->index; 233 234 return sprintf(buf, "%d\n", !!(data->fan_status[nr] 235 & FAN_STATUS_LOSPD)); 236 } 237 238 static ssize_t show_fan_fault(struct device *dev, struct device_attribute 239 *devattr, char *buf) 240 { 241 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 242 struct pc87427_data *data = pc87427_update_device(dev); 243 int nr = attr->index; 244 245 return sprintf(buf, "%d\n", !!(data->fan_status[nr] 246 & FAN_STATUS_STALL)); 247 } 248 249 static ssize_t set_fan_min(struct device *dev, struct device_attribute 250 *devattr, const char *buf, size_t count) 251 { 252 struct pc87427_data *data = dev_get_drvdata(dev); 253 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 254 int nr = attr->index; 255 unsigned long val = simple_strtoul(buf, NULL, 10); 256 int iobase = data->address[LD_FAN]; 257 258 mutex_lock(&data->lock); 259 outb(BANK_FM(nr), iobase + PC87427_REG_BANK); 260 /* The low speed limit registers are read-only while monitoring 261 is enabled, so we have to disable monitoring, then change the 262 limit, and finally enable monitoring again. */ 263 outb(0, iobase + PC87427_REG_FAN_STATUS); 264 data->fan_min[nr] = fan_to_reg(val); 265 outw(data->fan_min[nr], iobase + PC87427_REG_FAN_MIN); 266 outb(FAN_STATUS_MONEN, iobase + PC87427_REG_FAN_STATUS); 267 mutex_unlock(&data->lock); 268 269 return count; 270 } 271 272 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan_input, NULL, 0); 273 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_input, NULL, 1); 274 static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, show_fan_input, NULL, 2); 275 static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, show_fan_input, NULL, 3); 276 static SENSOR_DEVICE_ATTR(fan5_input, S_IRUGO, show_fan_input, NULL, 4); 277 static SENSOR_DEVICE_ATTR(fan6_input, S_IRUGO, show_fan_input, NULL, 5); 278 static SENSOR_DEVICE_ATTR(fan7_input, S_IRUGO, show_fan_input, NULL, 6); 279 static SENSOR_DEVICE_ATTR(fan8_input, S_IRUGO, show_fan_input, NULL, 7); 280 281 static SENSOR_DEVICE_ATTR(fan1_min, S_IWUSR | S_IRUGO, 282 show_fan_min, set_fan_min, 0); 283 static SENSOR_DEVICE_ATTR(fan2_min, S_IWUSR | S_IRUGO, 284 show_fan_min, set_fan_min, 1); 285 static SENSOR_DEVICE_ATTR(fan3_min, S_IWUSR | S_IRUGO, 286 show_fan_min, set_fan_min, 2); 287 static SENSOR_DEVICE_ATTR(fan4_min, S_IWUSR | S_IRUGO, 288 show_fan_min, set_fan_min, 3); 289 static SENSOR_DEVICE_ATTR(fan5_min, S_IWUSR | S_IRUGO, 290 show_fan_min, set_fan_min, 4); 291 static SENSOR_DEVICE_ATTR(fan6_min, S_IWUSR | S_IRUGO, 292 show_fan_min, set_fan_min, 5); 293 static SENSOR_DEVICE_ATTR(fan7_min, S_IWUSR | S_IRUGO, 294 show_fan_min, set_fan_min, 6); 295 static SENSOR_DEVICE_ATTR(fan8_min, S_IWUSR | S_IRUGO, 296 show_fan_min, set_fan_min, 7); 297 298 static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_fan_alarm, NULL, 0); 299 static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_fan_alarm, NULL, 1); 300 static SENSOR_DEVICE_ATTR(fan3_alarm, S_IRUGO, show_fan_alarm, NULL, 2); 301 static SENSOR_DEVICE_ATTR(fan4_alarm, S_IRUGO, show_fan_alarm, NULL, 3); 302 static SENSOR_DEVICE_ATTR(fan5_alarm, S_IRUGO, show_fan_alarm, NULL, 4); 303 static SENSOR_DEVICE_ATTR(fan6_alarm, S_IRUGO, show_fan_alarm, NULL, 5); 304 static SENSOR_DEVICE_ATTR(fan7_alarm, S_IRUGO, show_fan_alarm, NULL, 6); 305 static SENSOR_DEVICE_ATTR(fan8_alarm, S_IRUGO, show_fan_alarm, NULL, 7); 306 307 static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, show_fan_fault, NULL, 0); 308 static SENSOR_DEVICE_ATTR(fan2_fault, S_IRUGO, show_fan_fault, NULL, 1); 309 static SENSOR_DEVICE_ATTR(fan3_fault, S_IRUGO, show_fan_fault, NULL, 2); 310 static SENSOR_DEVICE_ATTR(fan4_fault, S_IRUGO, show_fan_fault, NULL, 3); 311 static SENSOR_DEVICE_ATTR(fan5_fault, S_IRUGO, show_fan_fault, NULL, 4); 312 static SENSOR_DEVICE_ATTR(fan6_fault, S_IRUGO, show_fan_fault, NULL, 5); 313 static SENSOR_DEVICE_ATTR(fan7_fault, S_IRUGO, show_fan_fault, NULL, 6); 314 static SENSOR_DEVICE_ATTR(fan8_fault, S_IRUGO, show_fan_fault, NULL, 7); 315 316 static struct attribute *pc87427_attributes_fan[8][5] = { 317 { 318 &sensor_dev_attr_fan1_input.dev_attr.attr, 319 &sensor_dev_attr_fan1_min.dev_attr.attr, 320 &sensor_dev_attr_fan1_alarm.dev_attr.attr, 321 &sensor_dev_attr_fan1_fault.dev_attr.attr, 322 NULL 323 }, { 324 &sensor_dev_attr_fan2_input.dev_attr.attr, 325 &sensor_dev_attr_fan2_min.dev_attr.attr, 326 &sensor_dev_attr_fan2_alarm.dev_attr.attr, 327 &sensor_dev_attr_fan2_fault.dev_attr.attr, 328 NULL 329 }, { 330 &sensor_dev_attr_fan3_input.dev_attr.attr, 331 &sensor_dev_attr_fan3_min.dev_attr.attr, 332 &sensor_dev_attr_fan3_alarm.dev_attr.attr, 333 &sensor_dev_attr_fan3_fault.dev_attr.attr, 334 NULL 335 }, { 336 &sensor_dev_attr_fan4_input.dev_attr.attr, 337 &sensor_dev_attr_fan4_min.dev_attr.attr, 338 &sensor_dev_attr_fan4_alarm.dev_attr.attr, 339 &sensor_dev_attr_fan4_fault.dev_attr.attr, 340 NULL 341 }, { 342 &sensor_dev_attr_fan5_input.dev_attr.attr, 343 &sensor_dev_attr_fan5_min.dev_attr.attr, 344 &sensor_dev_attr_fan5_alarm.dev_attr.attr, 345 &sensor_dev_attr_fan5_fault.dev_attr.attr, 346 NULL 347 }, { 348 &sensor_dev_attr_fan6_input.dev_attr.attr, 349 &sensor_dev_attr_fan6_min.dev_attr.attr, 350 &sensor_dev_attr_fan6_alarm.dev_attr.attr, 351 &sensor_dev_attr_fan6_fault.dev_attr.attr, 352 NULL 353 }, { 354 &sensor_dev_attr_fan7_input.dev_attr.attr, 355 &sensor_dev_attr_fan7_min.dev_attr.attr, 356 &sensor_dev_attr_fan7_alarm.dev_attr.attr, 357 &sensor_dev_attr_fan7_fault.dev_attr.attr, 358 NULL 359 }, { 360 &sensor_dev_attr_fan8_input.dev_attr.attr, 361 &sensor_dev_attr_fan8_min.dev_attr.attr, 362 &sensor_dev_attr_fan8_alarm.dev_attr.attr, 363 &sensor_dev_attr_fan8_fault.dev_attr.attr, 364 NULL 365 } 366 }; 367 368 static const struct attribute_group pc87427_group_fan[8] = { 369 { .attrs = pc87427_attributes_fan[0] }, 370 { .attrs = pc87427_attributes_fan[1] }, 371 { .attrs = pc87427_attributes_fan[2] }, 372 { .attrs = pc87427_attributes_fan[3] }, 373 { .attrs = pc87427_attributes_fan[4] }, 374 { .attrs = pc87427_attributes_fan[5] }, 375 { .attrs = pc87427_attributes_fan[6] }, 376 { .attrs = pc87427_attributes_fan[7] }, 377 }; 378 379 static ssize_t show_name(struct device *dev, struct device_attribute 380 *devattr, char *buf) 381 { 382 struct pc87427_data *data = dev_get_drvdata(dev); 383 384 return sprintf(buf, "%s\n", data->name); 385 } 386 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); 387 388 389 /* 390 * Device detection, attach and detach 391 */ 392 393 static void __devinit pc87427_init_device(struct device *dev) 394 { 395 struct pc87427_data *data = dev_get_drvdata(dev); 396 int i; 397 u8 reg; 398 399 /* The FMC module should be ready */ 400 reg = pc87427_read8(data, LD_FAN, PC87427_REG_BANK); 401 if (!(reg & 0x80)) 402 dev_warn(dev, "FMC module not ready!\n"); 403 404 /* Check which fans are enabled */ 405 for (i = 0; i < 8; i++) { 406 reg = pc87427_read8_bank(data, LD_FAN, BANK_FM(i), 407 PC87427_REG_FAN_STATUS); 408 if (reg & FAN_STATUS_MONEN) 409 data->fan_enabled |= (1 << i); 410 } 411 412 if (!data->fan_enabled) { 413 dev_dbg(dev, "Enabling all fan inputs\n"); 414 for (i = 0; i < 8; i++) 415 pc87427_write8_bank(data, LD_FAN, BANK_FM(i), 416 PC87427_REG_FAN_STATUS, 417 FAN_STATUS_MONEN); 418 data->fan_enabled = 0xff; 419 } 420 } 421 422 static int __devinit pc87427_probe(struct platform_device *pdev) 423 { 424 struct pc87427_data *data; 425 struct resource *res; 426 int i, err; 427 428 if (!(data = kzalloc(sizeof(struct pc87427_data), GFP_KERNEL))) { 429 err = -ENOMEM; 430 printk(KERN_ERR DRVNAME ": Out of memory\n"); 431 goto exit; 432 } 433 434 /* This will need to be revisited when we add support for 435 temperature and voltage monitoring. */ 436 res = platform_get_resource(pdev, IORESOURCE_IO, 0); 437 if (!request_region(res->start, res->end - res->start + 1, DRVNAME)) { 438 err = -EBUSY; 439 dev_err(&pdev->dev, "Failed to request region 0x%lx-0x%lx\n", 440 (unsigned long)res->start, (unsigned long)res->end); 441 goto exit_kfree; 442 } 443 data->address[0] = res->start; 444 445 mutex_init(&data->lock); 446 data->name = "pc87427"; 447 platform_set_drvdata(pdev, data); 448 pc87427_init_device(&pdev->dev); 449 450 /* Register sysfs hooks */ 451 if ((err = device_create_file(&pdev->dev, &dev_attr_name))) 452 goto exit_release_region; 453 for (i = 0; i < 8; i++) { 454 if (!(data->fan_enabled & (1 << i))) 455 continue; 456 if ((err = sysfs_create_group(&pdev->dev.kobj, 457 &pc87427_group_fan[i]))) 458 goto exit_remove_files; 459 } 460 461 data->hwmon_dev = hwmon_device_register(&pdev->dev); 462 if (IS_ERR(data->hwmon_dev)) { 463 err = PTR_ERR(data->hwmon_dev); 464 dev_err(&pdev->dev, "Class registration failed (%d)\n", err); 465 goto exit_remove_files; 466 } 467 468 return 0; 469 470 exit_remove_files: 471 for (i = 0; i < 8; i++) { 472 if (!(data->fan_enabled & (1 << i))) 473 continue; 474 sysfs_remove_group(&pdev->dev.kobj, &pc87427_group_fan[i]); 475 } 476 exit_release_region: 477 release_region(res->start, res->end - res->start + 1); 478 exit_kfree: 479 platform_set_drvdata(pdev, NULL); 480 kfree(data); 481 exit: 482 return err; 483 } 484 485 static int __devexit pc87427_remove(struct platform_device *pdev) 486 { 487 struct pc87427_data *data = platform_get_drvdata(pdev); 488 struct resource *res; 489 int i; 490 491 hwmon_device_unregister(data->hwmon_dev); 492 device_remove_file(&pdev->dev, &dev_attr_name); 493 for (i = 0; i < 8; i++) { 494 if (!(data->fan_enabled & (1 << i))) 495 continue; 496 sysfs_remove_group(&pdev->dev.kobj, &pc87427_group_fan[i]); 497 } 498 platform_set_drvdata(pdev, NULL); 499 kfree(data); 500 501 res = platform_get_resource(pdev, IORESOURCE_IO, 0); 502 release_region(res->start, res->end - res->start + 1); 503 504 return 0; 505 } 506 507 508 static struct platform_driver pc87427_driver = { 509 .driver = { 510 .owner = THIS_MODULE, 511 .name = DRVNAME, 512 }, 513 .probe = pc87427_probe, 514 .remove = __devexit_p(pc87427_remove), 515 }; 516 517 static int __init pc87427_device_add(unsigned short address) 518 { 519 struct resource res = { 520 .start = address, 521 .end = address + REGION_LENGTH - 1, 522 .name = logdev_str[0], 523 .flags = IORESOURCE_IO, 524 }; 525 int err; 526 527 pdev = platform_device_alloc(DRVNAME, address); 528 if (!pdev) { 529 err = -ENOMEM; 530 printk(KERN_ERR DRVNAME ": Device allocation failed\n"); 531 goto exit; 532 } 533 534 err = platform_device_add_resources(pdev, &res, 1); 535 if (err) { 536 printk(KERN_ERR DRVNAME ": Device resource addition failed " 537 "(%d)\n", err); 538 goto exit_device_put; 539 } 540 541 err = platform_device_add(pdev); 542 if (err) { 543 printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n", 544 err); 545 goto exit_device_put; 546 } 547 548 return 0; 549 550 exit_device_put: 551 platform_device_put(pdev); 552 exit: 553 return err; 554 } 555 556 static int __init pc87427_find(int sioaddr, unsigned short *address) 557 { 558 u16 val; 559 int i, err = 0; 560 561 /* Identify device */ 562 val = force_id ? force_id : superio_inb(sioaddr, SIOREG_DEVID); 563 if (val != 0xf2) { /* PC87427 */ 564 err = -ENODEV; 565 goto exit; 566 } 567 568 for (i = 0; i < 2; i++) { 569 address[i] = 0; 570 /* Select logical device */ 571 superio_outb(sioaddr, SIOREG_LDSEL, logdev[i]); 572 573 val = superio_inb(sioaddr, SIOREG_ACT); 574 if (!(val & 0x01)) { 575 printk(KERN_INFO DRVNAME ": Logical device 0x%02x " 576 "not activated\n", logdev[i]); 577 continue; 578 } 579 580 val = superio_inb(sioaddr, SIOREG_MAP); 581 if (val & 0x01) { 582 printk(KERN_WARNING DRVNAME ": Logical device 0x%02x " 583 "is memory-mapped, can't use\n", logdev[i]); 584 continue; 585 } 586 587 val = (superio_inb(sioaddr, SIOREG_IOBASE) << 8) 588 | superio_inb(sioaddr, SIOREG_IOBASE + 1); 589 if (!val) { 590 printk(KERN_INFO DRVNAME ": I/O base address not set " 591 "for logical device 0x%02x\n", logdev[i]); 592 continue; 593 } 594 address[i] = val; 595 } 596 597 exit: 598 superio_exit(sioaddr); 599 return err; 600 } 601 602 static int __init pc87427_init(void) 603 { 604 int err; 605 unsigned short address[2]; 606 607 if (pc87427_find(0x2e, address) 608 && pc87427_find(0x4e, address)) 609 return -ENODEV; 610 611 /* For now the driver only handles fans so we only care about the 612 first address. */ 613 if (!address[0]) 614 return -ENODEV; 615 616 err = platform_driver_register(&pc87427_driver); 617 if (err) 618 goto exit; 619 620 /* Sets global pdev as a side effect */ 621 err = pc87427_device_add(address[0]); 622 if (err) 623 goto exit_driver; 624 625 return 0; 626 627 exit_driver: 628 platform_driver_unregister(&pc87427_driver); 629 exit: 630 return err; 631 } 632 633 static void __exit pc87427_exit(void) 634 { 635 platform_device_unregister(pdev); 636 platform_driver_unregister(&pc87427_driver); 637 } 638 639 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>"); 640 MODULE_DESCRIPTION("PC87427 hardware monitoring driver"); 641 MODULE_LICENSE("GPL"); 642 643 module_init(pc87427_init); 644 module_exit(pc87427_exit); 645